This invention relates to a pulsating spray head for attachment to a source of fluid under pressure, in particular water.
A number of prior art pulsating spray heads are known, some using a swash plate and others using rotors. Some of these are quite complex or do not provide effective pressure fluctuations.
U.S. Pat. No. 3,734,410 of Bruno issued May 22, 1973 discloses a spray head which uses an oscillating plate (swash plate) mounted on a perforated cover. Water pressure causes the plate to oscillate and, as it oscillates, it sequentially blocks holes around the periphery of the cover. As only holes near the periphery can be blocked by the oscillating plate, large scale pressure fluctuations are not possible. The present invention uses a rolling conical disc which, as it rolls, substantially blocks radially extending holes in a plate. The structure is simple and enables effective pressure fluctuations.
Canadian Pat. No. 1,029,066 of Givler issued Apr. 4, 1978 discloses one arrangement which uses an oscillating plate with a projection which rests on the upper surface of a spray head. However, the plate can only block holes near the periphery of the spray head, unlike the present invention which can block an entire radially extending row of holes to provide effective pressure fluctuations.
Canadian Pat. No. 986,162 of Deines et al. issued Mar. 23, 1976 discloses the use of a hollow cylindrical valve rotor with turbine blades. The present invention does not require any turbine blades and is simpler than the structure disclosed by this patent.